When Xavier Cervantes was scouting properties in Napa, he looked in all the usual hallowed ground for vineyards: Oakville, Rutherford, Pritchard Hill. The Mexico City entrepreneur got close — in escrow — twice, once with a property on Atlas Peak, once on Howell Mountain. Both fell through at the 11th hour.

It took seven years, but after exhausting all other possibilities, Cervantes finally purchased an 1,100-acre ranch in the far eastern reaches of Napa County, the edge of the county’s viable viticultural land: Pope Valley.

Pope Valley has long been considered Napa’s less-desirable corner. Although grapes have grown there since the 19th century, it’s never been named an American Viticultural Area. Over the peak of Howell Mountain, as close to Middletown as it is to St. Helena, the area is rarely discussed, scarcely developed and largely written off as too hot for high-quality grape growing.

But as the Napa Valley floor grows ever more crowded, and its land values skyrocket, activity moves outward. Like Coombsville before it — Napa’s youngest sub-AVA, long neglected until a recent surge of interest — Pope Valley is the latest Napa region to rise from obscurity for the simple reason that it still has plantable land.

It may also be Napa’s last.

Cervantes’ estate, which he calls Hine Ranch, marks the highest-profile project yet to bottle an estate Pope Valley wine made at a Pope Valley winery. He’s hired Howard Backen (Harlan, Kenzo, Cliff Lede) to build a winery, a tractor barn, two homes and an equestrian center, and Andy Erickson (Ovid, Dalla Valle, Mayacamas) to make the wines. “I never thought I’d be making wine in Pope Valley,” says Erickson.

“For me, it’s like a fairy tale,” Cervantes says. In a bolero hat and cowboy boots, the real estate developer — who also owns Calahua, the world’s second-largest producer of coconut cream — looks the part of the frontiersman. And Hine, where wild deer and turkeys roam, has the feeling of an uncharted, feral frontier.

Photo: Noah Berger, Special To The Chronicle

Xavier Cervantes checks on the grapes growing in one of the vineyards on his Pope Valley ranch. He is producing Cabernet Sauvignon.

Xavier Cervantes checks on the grapes growing in one of the...

He’s not the only settler. Squeezed by similar pressures, other developers are moving into Pope Valley, too, to build golf courses, homes and hotels. The implications are complicated. Development draws mixed reactions. Grape prices are already rising, approaching the county average — sure to be reflected in increased bottle prices.

Cervantes believes he can finally do justice to one of Napa’s great, undiscovered terroirs. But this new interest in the viticultural fringes also poses a more ominous question. Is there nowhere left to plant?

Planting new vineyards in Napa today is no easy feat. Ninety-one percent of the county’s acreage is under some form of protection from development, whether zoned as Agricultural Preserve or Agriculture, Watershed and Open Space. What constitutes “development” has shifted over time. The act setting up the Ag Preserve, passed in 1968, positioned Napa land’s “highest and best use” as agricultural, as opposed to commercial real estate. But in recent years “development” has come to include agriculture itself.

While the county’s vineyard area ballooned from less than 12,000 acres when the Ag Preserve was established to over 45,000 today, that has remained virtually unchanged since the early 2000s. Want a vineyard in that 30-mile stretch between the cities of Napa and Calistoga, framed by Highway 29 and the Silverado Trail? Get in line. “The valley floor is considered ‘planted out,’” says Patsy McGaughy of Napa Valley Vintners.

The remaining plantable land is largely in Napa’s hillsides, which are under strict regulation to prevent erosion — soon potentially even stricter, if voters pass a proposed ballot measure that would severely limit future oak woodlands removal. More and more, it looks like very little of Napa County’s virgin land may ever be destined for grapevines.

Meanwhile, in the last 15 years, plantings in Pope Valley have increased by about 30 percent, estimates Josh Anstey, Hine’s vineyard manager. A Pope Valley resident since 1999, Anstey managed St. Supery’s Dollarhide Ranch, adjacent to Hine, before Chanel bought it in 2015.

In 1974, when Houston’s Butte Oil bought nearly 5,000 acres in Pope Valley, it was able to plant 900 acres of grapevines because it built a huge reservoir to feed them, establishing the Juliana Mutual Water Company. (The Juliana Vineyard has since changed hands several times and been divided into smaller parcels. Terlato Family is the current owner.) But ever since Lake Beryessa was built nearby, reservoir development has rarely been green-lighted.

“By the fall every year, a lot of homes here don’t have any more water,” Antsey says. “People have gotten pretty used to taking short showers.”

Other parts of Napa have struggled with water supply, too. A bitter, decade-long dispute over whether Hall Wines should be allowed to plant a new vineyard on Atlas Peak hinged, in part, on whether its water use would interfere with the sources that feed a nearby residential community.

Lucky for Xavier Cervantes, Hine Ranch has four reservoirs and five natural springs. He has rights to the water from a creek that runs through his property, too. But, he says, “I don’t actually think I will need it.”

Pope’s produce has long served as many Napa wineries’ secret ingredient: Because grape prices have historically been a fraction of those in the Napa Valley floor, it’s common to fill out ultra-premium Oakville Cabernet with a little bit of discount-bin Pope Valley fruit.

While most of Pope Valley was colonized long ago by big-name companies headquartered elsewhere — Chanel, Levi Strauss, Gallo, Hess, Terlato, Hall, Beringer — no one advertises the fruit source in their marketing materials.

The relationship of grape prices to the perception of quality, however, could already be changing. In 2012, when Cervantes bought Hine from contractor Ron Fredericks (for an undisclosed price), the property’s Cabernet Sauvignon grapes were selling for $1,900 a ton — a screaming deal in a county whose average Cabernet grape price reached $7,479 last year. But Cervantes believed the fruit was worth more. Last year, Oakville winery Sequoia Grove paid $7,000 a ton for Hine grapes. Typically, that would translate to a $70 bottle. (Though a price for Hine’s inaugural 2015 vintage of estate wine has not yet been set, all signs point to steep.)

It’s hard to imagine anyone drinking a $70 bottle of wine, let alone making one, when you drive through Pope Valley (population: 583). The town feels distinctly post-glory. Its boom time was the mid- to late 1800s, when its quicksilver mines thrived. It was a stagecoach stop between Middletown and Calistoga, and the blacksmith made his living fixing broken wagon wheels. In that era, resorts like Walter Springs, Samuel Springs and Aetna Springs (from whose grounds Ronald Reagan announced his gubernatorial campaign), made the area a vacation destination.

Today, the town’s commercial center consists of a convenience store, a post office and an auto body shop. To outsiders, Pope Valley is best known for its Thanksgiving turkey shoot, now discontinued, and a roadside collection of 5,000 hubcaps. Long-dilapidated buildings still advertise the businesses that housed them half a century ago. Everywhere, paint is chipping.

In other words, an incongruous backdrop for a rustic-chic Howard Backen blockbuster.

Can Pope Valley produce a great wine? Very possibly, and the young 2015 Hine has the markings of a textbook Napa Valley hillside wine: chewy tannins, deep black fruit, savory undertones of bay leaf and cedar, all with a plush, polished texture that is a signature of Andy Erickson. Yes, it’s hot here — the Vaca Mountains shield it from the coastal fog — but the area has a more dramatic diurnal shift than other parts of Napa, which helps grapes retain acid and color. It can be 105 degrees during the day and cool off to the 40s at night. “Valley” is a misnomer; many plantings, like Hine, are at an elevation of almost 1,000 feet.

Photo: Noah Berger, Special To The Chronicle

Andy Erickson, winemaker at Xavier Cervantes’ Hine Ranch vineyards.

Andy Erickson, winemaker at Xavier Cervantes’ Hine Ranch vineyards.

The deeper question is: What happens when Pope Valley does produce a great wine, and is recognized for it? That familiar narrative — new blood, rising quality, recognition, money — has few places to play out in Napa County. Land prices and wine prices hang in the balance. So, too, does the question of access: As Napa land grows more and more precious, who will be its gatekeepers, the ones who get to tell its stories and to determine its future?

After Pope, where does Napa go?

“For history, for hills and for logistical reasons,” Anstey says, “this really is the edge of grape-growing.”